To what extent is diabetes serious and mild, please provide reference data, thank you.

Whether diabetes is serious depends mainly on whether there are complications, such as diabetic nephropathy, retinopathy and neuropathy. If the blood sugar control is not ideal, the complications will be serious. There is no mild or severe diabetes in the textbook. I suggest you take a brief look at the basic knowledge of diabetes first. Many insulin manufacturers will give it to patients for free, and they can get it from the endocrinology department of the hospital for free.